Here's how it is being positioned: "The Sunday Times Social List is set to become the definitive measure of the most influential people within the social space."

Tricky. The trouble with measuring 'influence' is that it is incredibly difficult to do so in an automated way. I think it's virtually impossible to make any real statements about who is and isn't influential without some form of human analysis.

These tools are of course works in progress, and as they stand they are certainly indicators of something, but I'm not sure they're indicators of true influence.